A typical solution for the viewing of data contained in dense line graphs is to use a so-called “pan-and-zoom” interface. This technique is often used in interactive computer maps. Using this technique, the user can progressively zoom into a region of interest to view detail. One drawback to this technique is that the user quickly loses the global context of the entire data set as the region of interest is progressively zoomed. The user then has to zoom back out to again see the context, in order to choose a new region of interest to be zoomed.
An alternative technique is referred to as an “overview plus detail” interface. This technique provides a fixed overview of the entire dataset. The overview is used for selecting regions of interest. When a user selects a region of interest on the fixed overview, this causes a separate additional display to be created or updated in order to show the magnified details of the region of interest selected. Although this technique avoids data occlusion and distortions of the data, the user often has a difficult time cognitively maintaining the relationship between the separate displays. Also, this technique requires additional screen real estate to provide a space to display the additional views. As datasets become more dense in the number of data values, display screen real estate becomes more and more valuable, with less additional space available for such an additional view. This is particularly true in the case of oscilloscopes.
Oscilloscopes are being designed with increasingly larger data storage capacities. For example, it is currently possible, using the AGILENT INFINIUM 90000A (Agilent Technologies, Inc., Santa Clara, Calif.) series oscilloscope, to capture an oscilloscope trace consisting of 1 giga-points of data (i.e., 1×109 measurements). When very large amounts of data such as this are captured, this presents a problem in displaying the data on the relative modest screen sizes of the typical oscilloscope displays, as the data must be displayed very densely to fit it on the display, making it impossible to discern by the eye of the human user. When data capture amounts become very large, such as in the 1 giga-points example noted above, it is not even practical to provide a much larger display than that used by the typical oscilloscope, as this would still not provide the capability to display a view of the entire trace in full detail that would be readily discernible to the eye of the user.
Accordingly, there is a continuing need for improved systems, methods and techniques for displaying dense, time series graphs on a display in a way that a least a portion of the graph is displayed so that details of the portion can be readily discerned by a human user. This need applies not only to the oscilloscope field, but to other fields in which dense, time series graphs are produced, e.g., mass spectra, chromatograms, etc.